1. Field of the Invention
The present invention is in the field of photovoltaic panels. More particularly, the present invention is in the technical field of photovoltaic panel mounting systems.
2. Description of the Related Art
Photovoltaic, or solar, systems have emerged as a popular source of alternative energy. However, numerous deficiencies exist in current mounting devices and methods of installation. Striking a balance between customizability and efficiency of installation is paramount to the design and implementation of a successful photovoltaic system.
While many available photovoltaic systems are highly customizable, they lack in efficiency. Current installation methods, commonly referred to as build-on-site, require multiple steps taking place over several days of construction. First, workers must attach mounting devices to the surface or underlying substructure. Each additional mounting device requires penetration of the roof surface with a lag bolt, which compromises the roof's weather resistant barrier. Measurements are then taken and framing members are cut to length and mounted. Next, workers must measure, cut and install large amounts of wiring and component connections. Finally, photovoltaic modules are added individually until a completed photovoltaic array is formed. Each photovoltaic module must also be secured to the framework by additional mounting hardware. In many methods, this requires the added steps of inserting, positioning and tightening several nuts, bolts and washers per panel. Furthermore, addition of an aftermarket panel cleaning system results in added labor costs and risks possible damage to the installed photovoltaic panels.
In addition, the on-site installation of electrical wiring and power conversion elements creates unsafe working conditions for installers. When conventional string inverters are used as part of the system, the photovoltaic panels must be electrically connected in series as they are installed resulting in live, high-voltage, DC current on the roof. The use of string inverters also requires that extreme measures be taken to insure that all elements of the framing system are securely grounded. The installers must work around this live power to install additional strings of panels and their associated components. The large array of tools and components that must be loaded onto the sloped roof surface and controlled during installation makes build-on-site construction a complex and hazardous process.
Once installed, photovoltaic arrays are subjected to varying climates and must be able to withstand high winds and snow accumulation. Current systems, such as the one described above, are entirely dependent on the underlying roof surface to maintain their form. Additional mounting points can marginally increase the stability and load capacity of these build-on-site systems, but require additional penetrations to the roof surface. One of the major disadvantages to build on-site construction is that framing members exist as independent components rather than as an integrated framework. During installation the framing members are secured directly to the mounting devices without the added benefit of stabilizing cross members. Each row of photovoltaic panels is therefore mechanically independent from the adjacent rows. Because of this, many roof surface mounting points are required and there is no system wide load sharing. The inability to create an integrated framework makes build-on-site systems inefficient for carrying high wind and snow loads.
The increased demand for solar systems brings with it a need for a safer and more efficient means of producing and deploying them. Therefore, a need exists in the industry for a new and useful integrated, multi-module, photovoltaic mounting system capable of off-site prefabrication, transportation and installation as a unitized assembly.